Elan announced yesterday that two directors, Jack Schuler and Vaughn Bryson, had resigned from its board.

In a statement to the Irish Stock Exchange, Elan said the men had departed “in accordance with their previously announced intention and their related agreements with Elan”.

Mr Schuler and Mr Bryson, seen as dissident shareholders, were appointed to the Elan board only last year as part of an agreement to settle a campaign by some shareholders against the way the company was being run.

Within months, the men raised new issues. A report by US law firm McKenna Long Aldridge cleared the firm of breaking any regulations.

Separately, Elan confirmed yesterday that it expects to name a new chairman of its board before the end of the year.